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Perfect for variable spring conditions

Familiarity:
I've put it through the wringer

Fit:
True to size

I got the H2 Flow for sailing. I needed a jacket that would keep me warm during predawn starts but was able to dump tons of heat when you are sitting on a long stale air downwind run. While it is water resistant it by no means is waterproof but it doesn't really claim to be. It is a bit more of an athletic cut.

Have an answer for Grant Kates?

Lightweight, but well-insulated

Familiarity:
I've put it through the wringer

Fit:
True to size

As part of Abilyn Racing (http://www.abilynracing.com), a sailing team based in New York, my co-skipper and I first began wearing the H2 Flow jacket in mid-April, when the weather in the northeast U.S. was still fairly cold.

The jacket has served us well as both a mid-layer and outer-layer sailing jacket. The material of the jacket is not only very lightweight, but very well-insulated given the unique design.

We tested the jacket in a wide-range of conditions including temperatures down to about 35 degrees F. The H2 Flow coupled with HH Warm baselayer gear is our go-to combination of initial layers for cold-weather sailing, and can be utilized equally to other outdoor sports.

As temperatures warm up and base layers are shed, the H2 Flow allows you to expel heat through two vents located on the torso. These do a good job, but we'd much prefer those vents to be located under the arm pits to maximize heat dissipation.

Overall, we're quite satisfied with both the look and feel of the H2 Flow jacket. Keep an eye out on the outer material. Because the material is thin, it tends to get snagged in luggage zippers.